1. Field of the Invention
The present invention relates to a ceramic substrate that has a small relative misalignment between conductor layers formed on the surface and the back of a substrate body made of ceramic and includes the conductor layers formed with high positional accuracy, and a method of manufacturing the ceramic substrate.
2. Description of Related Art
To reduce a misalignment between layers of a plurality of ceramic green sheets and to suppress the deterioration of electrical characteristics caused by the misalignment of wiring patterns between the layers, there is proposed a method of manufacturing a ceramic multilayer wiring board. The method includes a first process for forming a plurality of print positioning/reading recognition holes in a ceramic green sheet becoming the lowermost layer later; a second process for detecting print positions by image processing on the basis of the recognition holes as the reference and printing wiring patterns on the surface of the green sheet; a third process for temporarily attaching a ceramic green sheet, which forms the next layer including windows larger than the recognition holes at the positions corresponding to the positions of the recognition holes in advance, to the green sheet; and a fourth process for detecting print positions by image processing through the windows on the basis of the recognition holes as the reference and printing wiring patterns on the surface of the green sheet forming the next layer. Further, in the method, wiring patterns are printed on a required number of ceramic green sheets through the repetition of the third and fourth processes (for example, see JP-A-2001-339160 (pages 1 to 7, FIGS. 1 (1) to (5)).
However, according to the method of manufacturing the ceramic wiring substrate, it is possible to accurately set the print positions of the wiring patterns between the plurality of green sheets but it is very difficult to accurately form a conductor layer at each predetermined position in plan view on both the surface and the back of the substrate body where a plurality of ceramic layers are laminated.
For example, in the above-mentioned method, it is very difficult to form conductor layers at the same positions in plan view on both the surface and the back of the substrate body with high positional accuracy.